Since its founding in 1948, the World Health Organization (WHO) has achieved many significant successes in curbing infectious diseases. Among the most outstanding is undoubtedly the official declaration in 1980 of the eradication of smallpox, which until then had claimed the lives of approximately 2 million people worldwide each year. The goal of elimination, formulated in 1967, was achieved through an internationally organized mass vaccination program — and it continues to serve as a model for campaigns designed to encourage the international community to vaccinate against the most threatening infectious diseases.

Since its inception, one of the organization’s core tasks has been the containment of outbreaks. It coordinates measures to combat dangerous and regionally widespread infectious diseases such as malaria, HIV/AIDS, polio, and tuberculosis; supports research into emerging or re-emerging pathogens such as the dengue and chikungunya viruses; and monitors pathogens such as SARS-CoV-2 and influenza viruses. In this context, it also works to provide protective equipment, medicines, and vaccines; supports health systems and authorities in fulfilling their responsibilities; and makes expertise, personnel, and materials available to address health crises.

However, the WHO is much more than just a simple disease control agency. It is the only organization capable of coordinating a response to health threats of global proportions — even when individual countries opt out of these efforts. This was most recently demonstrated during the COVID pandemic.

Critics of the WHO’s allegedly too-slow and overly diplomacy-oriented response to the first infections with the newly identified SARS-CoV-2 often forget that the agency can only issue recommendations. The implementation of these recommendations, however, depends solely on the member states, many of which acted inadequately or with delay in combating the pandemic.

Until recently, every member state except Liechtenstein, the small landlocked microstate in Central Europe, was represented in this specialized United Nations agency. But in January 2026, the US withdrew, following a decision first announced 5 years earlier during President Trump’s first term. Argentina then exited in March. The US had long been among the WHO’s most significant financial supporters, helping fund a wide range of projects around the world.

Starting in 2023, however, other major donor countries such as Germany, France, and the UK also sharply reduced their contributions. Overall, this led to a 40% reduction in available funding — with disastrous consequences for global health programs. Two recent examples illustrate particularly clearly just how important adequate funding for the WHO is for effectively addressing global health threats.

Two Outbreaks, Shared High-Risk Features

In recent weeks, the international community has been confronted with two health crises that have received significant media attention: the Ebola outbreak in the Democratic Republic of the Congo (DRC) caused by the Bundibugyo virus (BDBV), which is still ongoing, and the outbreak of hantavirus infections of the Andes virus variant on the cruise ship “MV Hondius.”

The two outbreaks share several similarities. Both involve diseases caused by highly pathogenic viruses that are transmissible from person to person and are fatal in up to 50% of cases, and the intense media coverage has raised fears that a new pandemic might even be looming. A brief review of the events.

BDBV Outbreak in DRC, Uganda

In late April, several cases of hemorrhagic fever emerged in the DRC; on May 15, local health authorities finally confirmed their suspicion that the infections might be Ebola. The BDBV was identified as the cause. There are no specific treatments for the virus, and a vaccine is not yet available. BDBV infections are fatal in about 40% of those infected.

On May 17, the WHO finally classified the outbreak as a Public Health Emergency of International Concern. The outbreak likely began in the third week of April, according to the relevant authorities, and has since spread to the neighboring country of Uganda. Most recently, 676 confirmed cases and well over 100 suspected cases were reported in the DRC, with 136 patients having died; Uganda has so far reported 19 cases and two deaths. The actual number of infections is likely to be much higher, however, as testing capacity is lacking in many parts of the region and some patients avoid contact with the local healthcare system.

To prevent further spread across national borders, one proposal has been to close the border crossings in the affected region. As sensible as this demand may seem at first glance, it fails to take local conditions into account and could even increase the risk for undetected transmission. This is due to local particularities that stakeholders without in-depth knowledge of the region tend to overlook.

There is heavy cross-border traffic between the DRC and its neighbors, Uganda and South Sudan, driven by trade and people employed in the region’s gold mines. Ituri Province, the epicenter of the current outbreak, borders Uganda to the east and South Sudan to the northeast. For more than two decades, the region has been marked by recurring armed conflicts, which have resulted in approximately 1.7 million people becoming internally displaced.

Over the past year, the clashes have intensified, resulting in 100,000 new internally displaced persons. According to experts familiar with regional conditions, border closures would very likely lead to illegal border crossings. Infected and sick individuals could then no longer be identified through border controls, which would facilitate uncontrolled spread.

Regionally, outbreak management is primarily handled by staff of the Africa Centers for Disease Control and Prevention. As part of the African Union, this intergovernmental health agency is responsible for public health, prevention, and control of infectious diseases across the five African health regions. It works in close coordination with the WHO to ensure the effective implementation of joint strategies and the best possible allocation of resources to member states.

Currently, the main challenges lie in contact tracing — as a result, infections are spreading unnoticed, and local aid organizations are consequently struggling to keep up with containment efforts. For this reason, the WHO plans to invest $518 million (USD) in combating the outbreak over the next 6 months. Among other things, the funds will be used to develop a vaccine against the BDBV.

Andes Hantavirus Outbreak on MV Hondius

Another life-threatening viral disease caused concern among health authorities in several countries in April.

In early April, several passengers and a ship’s doctor on the cruise ship MV Hondius developed severe respiratory illnesses caused by infections with the Andes hantavirus (ANDV). The ship had departed from Ushuaia, Argentina, and made several stops along its route through the South Atlantic, during which passengers disembarked before the virus could be identified.

The first patient died on the ship on April 26, at that time, the ANDV infection was still unknown. In the days and weeks that followed, additional people fell ill, and two died. A total of 11 cases of infection were confirmed.

With a case fatality rate of 40%, the ANDV is extremely dangerous, and it is the only hantavirus that can be transmitted from person to person. The incubation period is up to 6 weeks, and in some cases even longer. At the same time, the risk for transmission under everyday conditions remains very low: Infection requires close contact over an extended period. The most important reservoir host is a species of dwarf rice rat, Oligoryzomys longicaudatus, which is often persistently infected without showing symptoms. Other rodents can also carry the virus. All these species are native exclusively to South America.

It now appears clear that the initial transmission did not occur on board the ship, but on land — presumably in Ushuaia. The exact location, however, remains unknown — among other sites, a landfill has come under scrutiny by the authorities, who are now expanding their investigations to other regions. It is highly likely that further passengers became infected on the ship, where the confined space over an extended period and the inevitably closer contact between passengers and crew likely facilitated transmission.

Although the infected individuals and potential contacts were mainly on the ship, contact tracing proved difficult following the evacuation. The approximately 150 passengers on board and the ship’s crew represented 23 nations. Most of the passengers were able to return to their respective home countries on special flights and were required to self-isolate or enter quarantine facilities upon arrival.

About 30 passengers who had left the ship on the South Atlantic island of St Helena 2 weeks after the outbreak began to return to their home countries had to be tracked separately. The long incubation period, country-specific differences in quarantine regulations, and possible violations of these guidelines further complicated comprehensive infection surveillance.

To assess the situation and determine research priorities, a WHO-led emergency scientific consultation with experts took place on May 15. Subsequently, the WHO published a comprehensive assessment of the situation and recommendations for managing returning infected individuals, suspected cases, and close contacts. All patients are now receiving treatment in their home countries, and the majority of suspected cases have been able to end their self-isolation or quarantine.

WHO’s Role in Global High-Risk Outbreaks

Both outbreaks serve as a reminder of the importance the WHO continues to play — and will likely continue to play in the future — in managing international health crises with high-risk potential. However, the conditions under which the organization can operate must be urgently brought up-to-date to meet current requirements. This means that without the conclusion of the jointly drafted WHO Pandemic Agreement, the WHO’s ability to act is severely limited.

The fact that the agreement is still awaiting ratification is due to disagreement over an important supplementary agreement: The “Pathogen Access and Benefit-Sharing” annex is intended to ensure that access to samples of pathogens with pandemic potential and their genetic information is made equally available to all member states, so that the development of vaccines and medications is not driven solely by profit motives.

Delays like these contribute to preventable outbreaks. Experts recently wrote an open letter addressing this issue. It is addressed to “all heads of state and government, ministers of state, finance, and health, and heads of international organizations and agencies who have the authority to prevent and contain disease outbreaks” and highlights the failures that, in the wake of the COVID pandemic, have enabled the two current outbreaks as well as the spread of Mpox and make new pandemic events seem likely in the near future.

In the case of the Bundibugya Ebola epidemic, key commitments, such as providing diagnostic tools, vaccines, and treatments within 100 days of identifying a new threat, cannot be fulfilled, according to the signatories.

The letter makes it clear once again that future health crises with global implications will be difficult to manage if the WHO, the most important actor, cannot be equipped with sufficient resources and authority.

‘One Health’ Approach: Why Is Implementation Failing?

The fact that the two most recent outbreaks do not appear to pose a risk for pandemic spread is only partly due to the characteristics of the pathogens themselves. Above all, it is thanks to the efforts of all those involved in infection containment and surveillance that an even more widespread outbreak has been prevented so far.

The experience gained over many years in the affected countries has made rapid and targeted interventions possible in the first place: Argentine researchers first identified the Andes hantavirus in 1995, while scientists from the DRC have contributed to research on the BDBV and collected clinical data and treatment options.

Both outbreaks once again clearly demonstrate that interventions limited to a single country are doomed to fail in the fight against infectious diseases. Based on this understanding, the WHO — like most of its member states — has committed itself to the “One Health” approach. Essentially, this approach holds that the health of humans, animals, and the environment are closely interconnected, and that decisions regarding health and health policy must take these interrelationships into account.

The approach requires interdisciplinary and cross-border collaboration between human medicine, veterinary medicine, and the environmental sciences in order to address health challenges for everyone at all three levels.

However, the “One Health” concept is still far from being fully implemented, and attempts to establish it globally continue to face setbacks. The issue is not necessarily the premises underlying the approach, but — at least on the part of some actors — a display of power: questioning or distorting scientific findings; directly attacking and discrediting institutions that rely on scientific methods to fulfill their mandates — all of this creates uncertainty and mistrust.

The high-profile withdrawals of the US and Argentina from the WHO must also be viewed against this backdrop. This makes it important today to once again bring the significance of the WHO to the forefront and to defend its public health agenda when it is subjected to unwarranted attacks.

This story was translated from Univadis Germany, part of the Medscape Professional Network.